Technical Field
Embodiments of the subject matter disclosed herein relate to tractive effort for a plurality of wheels of a vehicle, for example.
Discussion of Art
Rail vehicles, such as locomotives, have a plurality of wheels configured to move along a rail, or track. Rail vehicles may pull large loads, such as multiple loaded rail cars, over long lengths of tracks. To operate efficiently, the rail vehicle is typically operated with a maximum of tractive effort. However, tractive effort is limited by the amount of contact friction between the wheels of the rail vehicle and the patch of rail over which the wheels are passing at any given moment. This amount of friction, in turn, depends such factors as the presence of contaminants (snow or ice, oil, mud, soil, etc.) on the rail or wheel, the shape (roundness) of the wheel, the shape of the rail, atmospheric temperature, humidity, and the normal force or weight imposed on an axle, among others.